Systems with the integer rounding property in normal monomial subrings
Commutative Algebra
2011-04-05 v2 Combinatorics
Abstract
Let C be a clutter and let A be its incidence matrix. If the linear system x>=0;xA<=1 has the integer rounding property, we give a description of the canonical module and the a-invariant of certain normal subrings associated to C. If the clutter is a connected graph, we describe when the aforementioned linear system has the integer rounding property in combinatorial and algebraic terms using graph theory and the theory of Rees algebras. As a consequence we show that the extended Rees algebra of the edge ideal of a bipartite graph is Gorenstein if and only if the graph is unmixed.
Cite
@article{arxiv.0803.1208,
title = {Systems with the integer rounding property in normal monomial subrings},
author = {Luis A. Dupont and Carlos Renteria-Marquez and Rafael H. Villarreal},
journal= {arXiv preprint arXiv:0803.1208},
year = {2011}
}
Comments
Major revision